Motor Assembly For A Powered Surgical Instrument
A surgical instrument is provided for cutting bone and other tissue. The surgical instrument is powered by a pressurized fluid and includes a rotatable shaft connected to a dissection tool. The instrument includes a housing member comprising a one-piece base. A rotor housing chamber is defined by the base, and the rotatable shaft is located in the rotor housing chamber. A first hearing housing is defined by the base, located adjacent the rotor housing chamber, and houses a first bearing that engages the rotatable shaft. A second bearing housing is defined by the base, located on an opposite side of the rotor housing chamber from the first bearing housing, and houses a second bearing that engages the rotatable shaft. A passage is defined by the base and operable to direct a pressurized fluid through the base to the rotor housing chamber in order to rotate the rotatable shaft.
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This application is a continuation of U.S. patent application Ser. No. 11/680,488 filed on Feb. 28, 2007. The entire disclosure of the above application is incorporated herein by reference.
FIELDThe present disclosure relates to surgical instruments and in particular to surgical instruments for dissecting bone and other tissue.
BACKGROUNDThis section provides background information related to the present disclosure which is not necessarily prior art.
Motorized surgical instruments may use a variety of methods to power moving components. For example, a motorized surgical instrument used for dissecting bone or tissue may use a pneumatic motor to power a dissecting tool. Pressurized fluid powers the motor, which may be mechanically linked to the dissecting tool by means of a rotatable shaft. The application of pressurized fluid to the motor results in rotation of the shaft, winch in turn rotates the dissecting tool.
Difficulties lay arise in the assembly and operation of pneumatic surgical instruments. Conventional pneumatic surgical instruments house the rotatable shaft in a rotor housing chamber defined by a rotor housing. in order to allow the shaft to rotate freely in the rotor housing chamber, a plural of components are coupled to the rotor housing such as, for example, bearings, bearing housings, fluid distributors, and a variety of other components known in the art. In addition, in order to ensure that these components are properly positioned in the assembly, an alignment pin may be used to align the components with the rotor housing and the shaft. As the number of components coupled to the rotor housing grows, the tolerance between the components and the rotor housing make the repeatability of the assembly of the surgical instrument itself difficult.
Therefore, what is needed is an improved assembly for a surgical instrument.
SUMMARYThis section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
The present disclosure provides many technological advances that can be used, either alone or in combination, to provide an improved motor assembly for a powered surgical instrument and/or an improved system and method for using powered surgical instruments.
In one embodiment, a housing member for a powered surgical instrument comprises a one-piece base, a rotor housing chamber defined by the base, a first bearing housing defined by the base and located adjacent the rotor housing chamber, a second bearing housing defined by the base and located on an opposite side of the rotor housing chamber from the first bearing housing, and a passage defused by the base and operable to direct a pressurized fluid through the base to the rotor housing chamber.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTIONExample embodiments will now be described more fully with reference to the accompanying drawings.
The present disclosure relates to surgical tools, and more particularly, to a housing member and motor assembly for use in powered surgical instruments. it is understood, however, that the following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples, This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
Referring initially to
With reference to
The surgical instrument 100 is shown connected to a hose assembly 108 for providing a source of pressurized fluid (e.g., air or nitrogen) to the motor assembly 102 through a tube 110 and a passageway 112 in the hpseassembly 108 for exhausting fluid after passing through the motor assembly 102. Typically, the hose assembly 108 is connected to a filter system (not shown) spaced from the patient and the exhaust fluid is allowed to exit the system after passing through the filter system. In the exemplary embodiments that will be described, the surgical instrument 100 is pneumatically powered. it is further understood, however, that many of the teachings discussed herein will have equal application for surgical instruments using other sources of power.
Referring now to
The motor assembly 102 further includes a bearing retainer member 300 having a bearing engagement surface 300a, a fastener 302 including a coupling member 302a, a first bearing 304 defining a first bearing aperture 304a, a plug 306, a rotatable shaft: 308 including a plurality of vanes 308a extending along its length and a pair of opposing coupling ends 308b and 308c, a bearing plate 310 defining a bearing plate aperture 310a, and a second bearing 312 defining a second bearing aperture 312a, all located in and/or coupled to a housing member 400 in a manner described in further detail below
Referring now to
Referring now particularly to
The first hearing 304 is located in the first hearing housing 406 and in engagement with the internal flange 410 such that the coupling end 308b of the rotatable shaft 308 extends into the first bearing aperture 304a and is rotatably supported by the first bearing 304. The coupling member 302a on the fastener 302 engages the coupling end 308b on the rotatable shaft 308 and the fastener 302 engages the first bearing 304. The bearing retainer member 300 is located partially in the first bearing housing 406 and the pressurized fluid inlet 404 such that the bearing engagement surface 300a engages the first bearing 304. The plug 306 is located in the passage opening 416a such that pressurized fluid in the passage 416 may not escape the passage 416 through the passage opening 416a. In the illustrated embodiment, the passage opening 416a is a result of the fabrication of the passage 416, which requires the passage 416 be drilled into the base 402 from the first end 402a of the housing member 402. The plug 306 is then press fit pernianently into the passage opening 416a in order to prevent pressurized fluid from escaping from the passage 416 through the passage opening 416a. However, alternative embodiments may include fabrication techniques for the passage 416 that eliminate the passage opening 416a and the need for the plug 306, such as the alternative embodiment 500 described below and illustrated in
With continued reference to
Pressurized fluid in the range of 0 to 150 PSI then enters the pressurized fluid inlet 404 from the tube 110 in the hose assembly 108, and a control may be provided to allow a user of the surgical instrument 100 to adjust the pressure of the pressurized fluid between this range. In an embodiment, the pressure of the pressurized fluid upstream of the motor assembly is set at 120 PSI. In an embodiment, the pressure of the pressurized fluid upstream of the motor assembly is set at 100 PSI. In an embodiment, pressure losses in the pressurized fluid upstream of the motor assembly may be between 10 to 30 PSI. The pressurized fluid is directed into the passage 416 through the passage entrance 418 due to the seal between the bearing retaining member 300 and the first bearing 304 and the seal between the plug 306 and the passage opening 416a. The pressurized fluid is then directed into the rotor housing chamber 412 through the o or housing fluid entrances 420. As the pressurized fluid moves through the rotor housing chamber 412 from the rotor housing fluid entrances 420 towards rotor housing fluid exits 422, the fluid impacts the vanes 308a and causes rotation of the rotatable. shaft 308, in an embodiment, the centerline of the rotatable shaft 308 may be offset from the centerline of the rotor housing chamber 412 in order to create increased torque relative to when the centerlines of the rotatable shaft 308 and the rotor housing chamber 412 are co-linear. The lower pressure fluid then exits the rotor housing chaMber 412 through the rotor housing fluid exits 422 and travels back through the exhaust fluid passageway 112 in the hose assembly 108 between the tube 110 and the hose assembly 108. In an embodiment, the fluid loses pressure due to expansion and energy exchange and may be, for example, between 20-30 PSI dynamic when the pressure of the fluid upstream of the motor assembly 102 is 120 PSI. Thus, a surgical instrument is provided that includes a housing member that allows for a simplified assembly of the motor assembly relative to a convention. rotor housing and decreases the passageways available to provide a fluid leak by reducing the number of components used in the motor assembly. While the surgical instrument 100 has been described as being powered pneumatically by a gas fluid, other powering schemes are contemplated such as, for example, hydraulically powering the surgical instrument with a liquid fluid.
Referring now to
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
Claims
1. An assembly for a motorized surgical instrument, the assembly comprising:
- a one-piece base having an external base wall extending along a first longitudinal axis between a first base end and a second base end and defining:
- a pressurized fluid inlet;
- a first bearing housing defined by the base and located adjacent to the first base end, the first bearing housing configured to receive a first bearing;
- a second bearing housing defined by the base and located adjacent to the second base end, the second bearing housing configured to receive a second bearing;
- a rotor housing chamber defined by the base between the first and second bearing housings, wherein the rotor housing chamber, the first bearing housing, the second bearing housing are one-piece with the one-piece base; and
- a passage defined by the base and configured to direct a pressurized fluid through the base to the rotor housing chamber.
2. The assembly of claim 1, wherein the passage extends along a second longitudinal axis and the second longitudinal axis is offset from and substantially parallel to the first longitudinal axis and extends along the pressurized fluid inlet, the first bearing housing and a portion of the rotor housing chamber.
3. The assembly of claim 1, further comprising:
- a passage entrance defined by the base and located between the first bearing housing and the pressurized fluid inlet, whereby pressurized fluid entering the pressurized fluid inlet enters the passage through the passage entrance.
4. The assembly of claim 3, wherein the passage entrance is oriented at a nonzero angle relative to the passage.
5. The assembly of claim 1, further comprising:
- a motor housing having a motor housing wall defining an internal bore, wherein the one-piece base is formed as a unitary piece and is configured to be positioned within the internal bore of the motor housing.
6. The assembly of claim 5, further comprising:
- a hose assembly having a tube inlet and an exhaust outlet, wherein the tube inlet is configured to connect to the motor housing and direct a pressurized fluid to the passage.
7. The assembly of claim 1, further comprising:
- a rotor housing fluid entrance defined by the base, whereby pressurized fluid in the passage enters the rotor housing chamber through the rotor housing fluid entrance; and
- a rotor housing fluid exit defined by the base, whereby fluid in the rotor housing chamber exits the rotor housing chamber through the rotor housing fluid exit.
8. The assembly of claim 1, further comprising:
- a transversely extending wall substantially perpendicular to the first longitudinal axis toward an interior of the one-piece base between the second bearing housing and the rotor housing chamber.
9. An assembly for a motorized surgical instrument, the assembly comprising:
- a one-piece base having an external base wall extending along a first longitudinal axis between a first base end and a second base end and defining: a pressurized fluid inlet; a first bearing housing defined by the base and located adjacent to the first base end; a second bearing housing defined by the base and located adjacent to the second base end; a rotor housing chamber defined by the base between the first and second bearing housings, wherein the rotor housing chamber, the first bearing housing, the second bearing housing are one-piece with the one-piece base; a passage defined by the base and configured to direct a pressurized fluid through the base to the rotor housing chamber;
- a first bearing located in the first bearing housing;
- a second bearing located in the second bearing housing; and
- a rotatable shaft located in the rotor housing chamber and engaging the first and second bearings.
10. The assembly of claim 9, wherein the one-piece base further comprises a bearing plate located in the second bearing housing and adjacent the second bearing.
11. The assembly of claim 9, further comprising:
- a fastener located at least partially in the first bearing housing and engaging the first bearing and the rotatable shaft.
12. The assembly of claim 9, further comprising:
- a bearing retainer member located at least partially in the first bearing housing and engaging the first bearing.
13. The assembly of claim 9, further comprising:
- a transversely extending wall substantially perpendicular to the first longitudinal axis toward an interior of the one-piece base between the second bearing housing and the rotor housing chamber.
14. The assembly of claim 9, further comprising:
- a passage entrance defined by the base and located between the first bearing housing and the pressurized fluid inlet, whereby pressurized fluid entering the pressurized fluid inlet enters the passage through the passage entrance.
15. The assembly of claim 9, wherein the one-piece base further comprises a rotor housing fluid entrance defined by the base, whereby pressurized fluid in the passage enters the rotor housing chamber through the rotor housing fluid entrance and engages the rotatable shaft; and
- wherein the one-piece base further comprises a rotor housing fluid exit defined by the base, whereby fluid in the rotor housing chamber exits the rotor housing chamber through the rotor housing fluid exit.
16. The assembly of claim 9, wherein the one-piece base further comprises a passage opening defined by the base and operable to accept a plug.
17. The assembly of claim 9, further comprising:
- a motor housing having a motor housing wall defining an internal bore, wherein the one-piece base is formed as a unitary piece and is configured to be positioned within the internal bore of the motor housing.
18. An assembly for a motorized surgical instrument, the assembly comprising:
- a one-piece base having an external base wall extending along a first longitudinal axis between a first base end and a second base end and defining:
- a pressurized fluid inlet adjacent to the first base end;
- a first bearing housing defined by the base and located adjacent to the pressurized fluid inlet, the first bearing housing configured to receive a first bearing;
- a second bearing housing defined by the base and located adjacent to the second base end, the second bearing housing configured to receive a second bearing;
- a rotor housing chamber defined by the base between the first and second bearing housings, wherein the rotor housing chamber, the first bearing housing, the second bearing housing are one-piece with the one-piece base; and
- a passage defined by the base and extending along a second longitudinal axis, wherein the second longitudinal axis is offset from and substantially parallel to the first longitudinal axis and extends along the pressurized fluid inlet, the first bearing housing and a portion of the rotor housing chamber; and
- a passage entrance defined by the base and located between the first bearing housing and the pressurized fluid inlet, whereby pressurized fluid entering the pressurized fluid inlet enters the passage through the passage entrance.
19. The assembly of claim 18, wherein the passage entrance is oriented at a nonzero angle relative to the passage.
20. The assembly of claim 18, further comprising:
- a motor housing having a motor housing wall defining an internal bore, wherein the one-piece base is formed as a unitary piece and is configured to be positioned within the internal bore of the motor housing.
Type: Application
Filed: Oct 14, 2013
Publication Date: Feb 13, 2014
Patent Grant number: 9668753
Applicant: Medtronic PS Medical, Inc. (Louisville, CO)
Inventors: Durrell G. TIDWELL (Burleson, TX), Jonathan Morris (Santa Rosa, CA), Gabriel A. Johnston (Raynham, MA)
Application Number: 14/053,013
International Classification: A61B 17/16 (20060101);